A new railway link between Oxford and London is being considered, which could provide relief for the county's road network.

The scheme proposed by Chiltern Railways will see new track installed at Bicester, linking its north-south route between Banbiry and London Marylebone, with the west-east line linking Oxford to Bletchley, which is served by local trains between Oxford and Bicester Town.

The proposal is seen by some industry experts as being a low-cost way of providing an alternative to building new roads. However, it would require investment to improve the track between Bicester and Oxford, via Islip. Trains take 26 minutes to make the 13-mile journey, due to speed restrictions.

Chiltern Railways' business development manager Andy Pearson said: "Originally we had a proposal to reopen the line from Princes Risborough through Wheatley to Oxford, but there are a number of major obstacles on that route and we feel it would be very difficult to justify the expense.

"We have submitted a number of suggestions to the Strategic Rail Authority, one of which was to put in a curve linking the lines at Bicester."

Should the link be built, Chiltern says it would mean a journey between Oxford and Marylebone would take about 70 minutes. First Great Western fast services between Oxford and London Paddington take about 55 minutes.

Another proposal Chiltern has considered in the past involves building a Parkway station, to attract motorists off the M40. It considered a link-up with the preserved Chinnor & Princes Risborough Railway, which would have seen it use the line on weekdays, to run trains to a new station close to the M40 junction at Lewknor.

Mr Pearson added: "Our reasoning is to provide an alternative route from north Oxfordshire into London. Many of the passengers using Bicester station are from Kidlington and this would be ideal for them."

Oxfordshire County Council is also supporting the plan. Rail development officer Adrian Saunders said: "We would welcome any increase in passenger services that would take traffic off the roads.

The proposed link remains on Chiltern Railways list of "asp- irations", but experts believe it is unlikely to get the green light before 2015 unless there is a major Government shift in funding from roads to railways.

Mike Greedy, regional director of the Rail Passengers Committee for Western England, said: "I would not be optimistic about seeing this scheme adopted in the short or medium term."